I think Its unlikely putting the LEDs in your Sys 1s would do any harm Cam
![no *.*](http://www.aussiepinball.com.au/Smileys/classic/no.gif)
they might flicker a bit though especially the GI.
They flicker in you Abracadbra because they are running on AC instead of DC voltage.
Personally, i wouldn't bother doing LEDs in my own games, mainly due to the expense but i also don't like the way they look in the older games like i have.
Putting LEDs into 17 machines??? No thankyou
![no *.*](http://www.aussiepinball.com.au/Smileys/classic/no.gif)